html, body {
  margin: 0; padding: 0; width: 100%; height: 100%;
  background: #000; overflow: hidden; touch-action: none;
  -webkit-user-select: none; user-select: none;
}
#app {
  position: fixed; inset: 0;
  display: flex; align-items: center; justify-content: center;
  background: #000;
}
canvas#game {
  background: #000;
  image-rendering: pixelated;
  image-rendering: -moz-crisp-edges;
  image-rendering: crisp-edges;
  touch-action: none;
}
#touchControls {
  position: fixed; inset: 0; pointer-events: none; display: none; z-index: 50;
}
.btn {
  position: absolute; pointer-events: auto;
  display: flex; align-items: center; justify-content: center;
  font-family: monospace; font-size: 22px; color: #fff;
  background: rgba(255,255,255,0.16); border: 2px solid rgba(255,255,255,0.45);
  border-radius: 10px; -webkit-user-select: none; user-select: none;
}
.btn:active { background: rgba(255,255,255,0.35); }
#btnUp    { left: 66px;  bottom: 158px; width: 52px; height: 52px; }
#btnDown  { left: 66px;  bottom: 30px;  width: 52px; height: 52px; }
#btnLeft  { left: 10px;  bottom: 94px;  width: 52px; height: 52px; }
#btnRight { left: 122px; bottom: 94px;  width: 52px; height: 52px; }
#btnAction {
  right: 30px; bottom: 60px; width: 84px; height: 84px; border-radius: 50%;
  background: rgba(90,220,140,0.25); border-color: rgba(140,255,180,0.6);
  font-size: 16px; font-weight: bold;
}
#btnPause {
  position: fixed; top: 10px; right: 10px; width: 38px; height: 32px;
  font-size: 15px; z-index: 60; pointer-events: auto; letter-spacing: 2px;
}
#rotateOverlay {
  position: fixed; inset: 0; z-index: 200; display: none;
  align-items: center; justify-content: center; flex-direction: column;
  background: #000; color: #fff; font-family: "DungGeunMo", "Malgun Gothic", monospace;
  text-align: center; padding: 20px; box-sizing: border-box;
}
#rotateOverlay .icon { font-size: 48px; margin-bottom: 12px; }
#rotateOverlay .msg { font-size: 18px; line-height: 1.6; }